Section lined pump shell for dredging



Dec. 12, 1944. CRAWFORD 2,365,058

SECTION LINED PUMP SHELL FOR DREDGING Filed June 4, 1945 2 Sheets-Sheet 1 1944' M. F. CRAWFORD 2,365,058

SECTION LINED PUMP SHELL FOR-DREDGING Filed June 4, 1945 v Z'Sheets-Sheet 2 ATTDRN EYS Patented Dec. 12, 1944 UNITED STATES :PATENT OFFICE.

SECTION LINED PUMP SHEI'JL FOR DREDGING Millard F. Crawford, Jackson, La.

' Application June 4, 1943',"Serial No. 489,678

3 Claims. I (Cl. 103-114) This invention relates to pumps and more particularly to a section lined pump shell for dredging pumps.

An object of the invention is to provide a complete liner for the inside of centrifugal pumps adapted to resist abrasive wear caused by the pumped material.

A further object is to provide a liner of this type which can be easily and quickly changed at small cost without welding which ordinarily character which will be formed of a few strong, simple and durable parts, which will be inexpensive to manufacture, and easily get out of order.

With the above and other objects in view the invention consists'of certainnovel details of construction and combinations of parts hereinafter fully described and claimed, it being understood that various modifications may be resorted to within the scope of the appended claims without departing from the spirit or sacrificing any of the advantages of the invention.

In the accompanying drawings forming a of this specification:

Figure l is a cross sectional view, with portions in elevation, of a centrifugal pump equipped with a sectional liner constructed in accordance with the invention.

Figure 2 is a longitudinal sectional view taken on the line 22 of Figure 1 with parts in elevation.

Figure 3 is a detail view partly in elevation and partly in section showing the keystone sector of the liner.

Referring now to the drawings in which like characters of reference designate similar parts in the various views, I designates the pump shell which is provided with supporting flanges I l whereby the pump may be anchored to a suitable foundation. The pump impeller 12, which rotates within the shell, is carried by a driven shaft l3. The face plates ll of the shell are bolted to flanges IS on the shell, the shaft l3 being passed through a stuffing box H3 in one of the face plates. An intake pipe I1 is provided with a flange l8 which is bolted to a flange l9 on the other face plate as shown at 20. An outlet pipe 2| is formed integral with the shell at a tangent thereto, see Figure 2. Water pipes 22 enter the first named face plate. These pump parts are conventional.

which will not part In centrifugal pumps of this type, as the pump material moves outwardly within the shell the to minimize the effects of the abrasion as well as to make it possible to remove the parts subjected to this abrasion as will now be described.

An annular lining 23, of abrasive resistant material is mounted on the inner peripheral wall of the shell and comprises a plurality of sectors 24 of U-shape in cross section, the side walls 25 of the sectors being thinner than the bottom portion 26 of the sectors, see Figure 1. The increased thickness of the bottom portion 26 is adapted to resist the maximum abrasion which occurs at the inner periphery of the shell II] where hydraulic pressure and velocity are greatest. The sectors are assembled in the shellas follows; beginning at the outlet pipe 2| the initial sector marked by the legend initial, and which is provided with an extension 21, is first inserted with the extension serving as a liner for the exhaust pipe. The second sector inserted also serves as a liner for the exhaust pipe and is marked by the legend second. The third, fourth, fifth and sixth sectors next laid in sequence are laid on the bottom of the pump shell and are marked with corresponding legends. Next the seventh to the sixteenth sectors are laid in sequence beginning on the opposite side of the initial sector from the second sector and are marked with corresponding legends. This leaves a wedge shaped space between the sixth and the seventeenth sectors for the reception of the keystone sector which is marked with a corresponding legend.

The keystone sector, see Figure 3, in provided with a long shank 28 which extends radially through a nipple 29 in the shell 10. The keystone sector is tapered on both sides to fit between the sixth and seventeenth sectors and tighten all of the sectors when a wedge 30 is driven through a slot 3| in the shank against a pair of metal washers 32 which are disposed on the shank and have a gasket 33 disposed between them on the shank and a second disk gasket 34 disposed between them and the nipple to prevent leakage from the shell.

In further carrying out the invention face plate liners 35 of suitable wear resisting material, are disposed inwardly of the face plates to receive rubbing contact of the impeller, see Figure 1. These liners are secured in place by cap screws 36 and adjusting screws 31 the latter carrying lock nuts 38. The adjusting screws are threaded through face plates and the cap screws are engaged through the adjusting screws and threaded into the liners. By slacking off all of the cap screws 36, and loosening the lock nuts 38, on the adjusting screws 31, the latter may be screwed in or out to adjust the face plate liners to any desired position. After the adjustment is made the lock nuts 38 and cap,screws 36 are retightenedto reserve; the adjustment.

The object of adjusting the face plate liners is to keep them very close to the impeller to prevent the water pressure from dropping. If the water pressure is not maintained the;abr.asive;rnatertal will work in between the impeller and the liners and wear out both rapidly. Withthis type got adjustment it is easy to keep the face plateliners very close to the impellers 0,11 :-.ither ;side,;a llgthe way round even though the impeller is not in perfect line with the shell.

f' Th materielfiom which-the.- liners ofr-thezshell z-an ut f plate is. constructed varie in a qr n -wit ;th mate ial' heinap mped -For exampl i a d mate ial be n pum ed th ,liners may :be donned ofracid :resisting material' will be fully understood without further explanation.

What is claimed is:

1. The combination with the U-shaped peripheral wall of a centrifugal pump shell, of U-shaped sectors having their legs relatively thinner than the bottoms of the sectors, said sectors being received against the inner peripheral wall of the shell, a tapered key vsector between two of the first named. sectors serving to wedge ,and maintain all the sectors in assembled position within ,the shell, all of said sectors being formed of abra- 'sive resisting material, a shank on the keystone ifiectnr engaged through an opening in the shell :ito project exteriorly of the shell, there being a -s 1ot in theshank outside of the shell, a wedge driven through said slot, a pair of metal washers tbetweemthegahell and the wedge, a gasket disposed.;b,etween the metal washers,.and a gasket -dlsposed between one of the metal washers and --&he shell.

I 2.;1Ibe -,c,ombina,tion :with ztbe -.=shell .of -a vcentrifugal pump, a curved lining iorethe shell, said ;,linin .having anfinnercurvature and: formed of ;sectors,one:of saidzsectors beinginthe form of a tapered "keystone; serving .to wedge and maintain the remaining sectors inrassembled position within-the shell, andmeans ioresecuringthe keytstone -,sect0r :to the shell.

3..';The structure,as oficlaimzland in which the means for securing the ikeystone :sector to the sshell comprises along:shank-.onithersector ensxesediradially through-the-she1l and having a .-s1 0t formedtherein outsideiohtheishell, awedge in said slot, .apairof metal washersdisposedon the shank underneath thewedge,1a.gasket dis- .posedt between .the washers, and .a -second gasket .dispqsed-hetween the washers .and: the shell. 

